Nonetheless, it moves.

In the sciences, the authority of thousands of opinions is not worth as much as one tiny spark of reason in an individual man.

To understand the Universe, you must understand the language in which it's written, the language of Mathematics.

But what exceeds all wonders, I have discovered four new planets and observed their proper and particular motions, different among themselves and from the motions of all the other stars; and these new planets move about another very large star [Jupiter] like Venus and Mercury, and perchance the other known planets, move about the Sun. As soon as this tract, which I shall send to all the philosophers and mathematicians as an announcement, is finished, I shall send a copy to the Most Serene Grand Duke, together with an excellent spyglass, so that he can verify all these truths.

By denying scientific principles, one may maintain any paradox.

If you could see the earth illuminated when you were in a place as dark as night, it would look to you more splendid than the moon.

Where the senses fail us, reason must step in.